<template>
    <div class="component-upload-image">
        <el-upload ref="imageUpload" :action="uploadImgUrl" :before-upload="handleBeforeUpload"
            :class="{ hide: fileList.length >= limit }" :file-list="fileList" :headers="headers" :limit="limit"
            :on-error="handleUploadError" :on-exceed="handleExceed" :on-preview="handlePictureCardPreview"
            :on-remove="handleDelete" :on-success="handleUploadSuccess" :show-file-list="true" list-type="picture-card"
            multiple>
            <i class="el-icon-plus"></i>
        </el-upload>

        <!-- 上传提示 -->
        <div v-if="showTip" slot="tip" class="el-upload__tip">
            请上传
            <template v-if="fileSize"> 大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b></template>
            <template v-if="fileType"> 格式为 <b style="color: #f56c6c">{{ fileType.join("/") }}</b></template>
            的文件
        </div>

        <el-dialog v-model="dialogVisible" append-to-body title="预览" width="800">
            <img :src="dialogImageUrl" style="display: block; max-width: 100%; margin: 0 auto" />
        </el-dialog>
    </div>
</template>

<script setup lang="ts">
import { getToken } from "@/utils/auth";
import { delOss, listByIds } from "@/api/system/oss";
import { ElLoading } from "element-plus";

const emits = defineEmits(["input"])
const imageUpload = ref()
const props = defineProps({
    value: String || Object || Array,
    // 图片数量限制
    limit: {
        type: Number,
        default: 5,
    },
    // 大小限制(MB)
    fileSize: {
        type: Number,
        default: 5,
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
        type: Array,
        default: () => ["png", "jpg", "jpeg"],
    },
    // 是否显示提示
    isShowTip: {
        type: Boolean,
        default: true
    }
})
const loadingInstance = ref()
let number = ref(0)
let uploadList = ref([])
let dialogImageUrl = ref("")
let dialogVisible = ref(false)
let hideUpload = ref(false)
// 上传的图片服务器地址
let uploadImgUrl = ref(import.meta.env.VITE_APP_TARGET_URL + "/resource/oss/upload")
let headers = ref({
    Authorization: "Bearer " + getToken()
})
let fileList = ref([])

watch(() => props.value, async (newValue, _oldValue) => {
    if (newValue) {
        // 首先将值转为数组
        let list;
        if (Array.isArray(newValue)) {
            list = newValue;
        } else {
            await listByIds(newValue).then(res => {
                list = res.data;
            })
        }
        // 然后将数组转为对象数组
        fileList.value = list.map(item => {
            // 此处name使用ossId 防止删除出现重名
            item = { name: item.ossId, url: item.url, ossId: item.ossId };
            return item;
        });
    } else {
        fileList.value = [];
        return [];
    }
}, { deep: true, immediate: true })

// 是否显示提示
const showTip = computed(() => {
    return props.isShowTip && (props.fileType || props.fileSize);
})

// 上传前loading加载
function handleBeforeUpload(file) {
    let isImg = false;
    if (props.fileType.length) {
        let fileExtension = "";
        if (file.name.lastIndexOf(".") > -1) {
            fileExtension = file.name.slice(file.name.lastIndexOf(".") + 1);
        }
        isImg = props.fileType.some(type => {
            if (file.type.indexOf(type) > -1) return true;
            if (fileExtension && fileExtension.indexOf(type) > -1) return true;
            return false;
        });
    } else {
        isImg = file.type.indexOf("image") > -1;
    }

    if (!isImg) {
        ElMessage.error(`文件格式不正确, 请上传${props.fileType.join("/")}图片格式文件!`);
        return false;
    }
    if (props.fileSize) {
        const isLt = file.size / 1024 / 1024 < props.fileSize;
        if (!isLt) {
            ElMessage.error(`上传头像图片大小不能超过 ${props.fileSize} MB!`);
            return false;
        }
    }
    loadingInstance.value = ElLoading.service({
        text: "正在上传图片，请稍候...",
        background: 'rgba(0, 0, 0, 0.7)',
    });
    number.value++;
}

// 文件个数超出
function handleExceed() {
    ElMessage.error(`上传文件数量不能超过 ${props.limit} 个!`);
}

// 上传成功回调
function handleUploadSuccess(res, file) {
    if (res.code === 200) {
        // @ts-ignore
        uploadList.value.push({ name: res.data.fileName, url: res.data.url, ossId: res.data.ossId });
        uploadedSuccessfully();
    } else {
        number.value--;
        loadingInstance.value.close()
        ElMessage.error(res.msg)
        imageUpload.value.handleRemove(file);
        uploadedSuccessfully()

    }
}
// 删除图片
function handleDelete(file) {
    const findex = fileList.value.map(f => f.name).indexOf(file.name);
    if (findex > -1) {
        let ossId = fileList.value[findex].ossId;
        delOss(ossId);
        fileList.value.splice(findex, 1);
        emits("input", listToString(fileList.value, ""));
    }
}
// 上传失败
function handleUploadError() {
    ElMessage.error("上传图片失败，请重试");
    loadingInstance.value.close()
}

// 上传结束处理
function uploadedSuccessfully() {
    if (number.value > 0 && uploadList.value.length === number.value) {
        fileList.value = fileList.value.concat(uploadList.value);
        uploadList.value = [];
        number.value = 0;
        emits("input", listToString(fileList.value, ""));
        loadingInstance.value.close()
    }
}
// 预览
function handlePictureCardPreview(file) {
    dialogImageUrl.value = file.url;
    dialogVisible.value = true;
}

// 对象转成指定字符串分隔
function listToString(list, separator) {
    let strs = "";
    separator = separator || ",";
    for (let i in list) {
        if (list[i].ossId) {
            strs += list[i].ossId + separator;
        }
    }
    return strs != "" ? strs.substr(0, strs.length - 1) : "";
}
</script>

<style lang="scss" scoped>
// .el-upload--picture-card 控制加号部分
:deep(.hide .el-upload--picture-card) {
    display: none;
}

// 去掉动画效果
:deep(.el-list-enter-active),
:deep(.el-list-leave-active) {
    transition: all 0s;
}

:deep(.el-list-enter),
.el-list-leave-active {
    opacity: 0;
    transform: translateY(0);
}
</style>

